D.G. Ritchie is known as one of the leading philosophers of British Idealism. Some scholars have regarded him as one of pivotal figures of the New Liberalism, whose prominent theorists were J. A. Hobson and L. T. Hobhouse. However, Hobson and Ritchie had different views on the justification of individual rights including rights of property. Whereas Ritchie criticized the abstractiveness of traditional natural rights theory and insisted that rights of property should be based on social arrangements which were to be judged by the common good of society, Hobson argued that every individual should be assigned by nature, as his natural property, that portion of his product required to sustain his productive energy.

Hume establishes the first principle in his study of human nature: ʻall our simple ideas proceed ... from their correspondent impressionsʼ（T 1.1.1.11）. It is so primary for his empiricism that based on it, he argues about space and time, a necessary connection between cause and effect, and even vice and virtue. But then why does he present the missing shade of blue as a contradictory example to it? In this paper, I will start by describing the resemblance thesis and the causal thesis involved in his first principle. I will then explain why the missing shade of blue is not a counterexample to the former thesis, but to the latter. Finally, I will argue why he does present the missing shade of blue though it does not affect his first principle.

In the Two Treatises of Government, Locke regards the right to charity as a natural right. This right allows a needy person to obtain from the surplus of a rich manʼs property the goods which are necessary for the preservation of his own life. The right to charity is a means to realizing the right of subsistence. Locke defines the right to charity as an imperfect right, or the kind of right which cannot be enforced. The idea of common charity, however, can be so utilized as to support the view that in case of necessity, political power could transfer goods from the rich to the poor.